Insulator



c SAURER Dec. 24, 1940.

TV UKATOR Filed April 4, 1938 INVENTOR (2712f (fizz/( r "21 ATToRNEYsmemes De c.24,1940 2,226,505

UNITED STATES PATENT I OFFICE msoul'roa Curt Saul-er, Akron. Ohio,assignor to The Firestone Tire & Rubber Company, Akron, Ohio, acorporation of Ohio 1 v Application April 4, 1938, Serial No. 199,867

1 Claim. (01. 287-85) This invention relates to insulators, and moremuiiier i2 and pipe i3. Another insulator (not especially it relates tovibration insulators suchshown) may be interposed between the frame Illas are utilized for supporting one body from or and the pipe thatconstitutes the inlet to the upon another body in such a manner thatvibramuiiier l2. As shown in Figure 1, one of the 5 tion of either bodyis not translated to the other. insulators I5 is under tension and theother is 5 Insulators of the character mentioned are ex undercompressive stress. Although the insulatensively used in motor vehiclesfor damping and tors function substantially as well in eitherposisuppressing vibration to the end that quietness of tion, thecompression position is preferable, and travel is achieved. Theinsulator constituting the it is in this position that the insulator isshown 10 subject matter of the present invention is especialin detail inFigures 2 and 3. m ly adapted to situations wherein the supported hinsul tor 5 consi ts primarily 0! a body load is of light weight, and isshown herein as of resilient vulcanized rubber, preferablycylinsupporting a vehicle mufiier and exhaust pipe from drical in form.Embedded in the rubber structhe frame of the vehicle, although it is notlimited ll adjacent e d re f, is a metal washer 1 to this particularuse. The insulator is shown ll, and secured to one face of said washer,as by both in a position where it is under tension, and welding, is anaxially disposed stud bolt it, said in a position where it is undercompression. It is bolt projecting beyond the adjacent end face of theunit that is under compression that will be the rubber structure. Therubber block i5 may illustrated and described in detail. be chemicallybonded to the washers I1 and stud The chief objects of the invention areto probolts IS in any of the known methods. Each 20 vide an improvedinsulator of the character menwasher I1 is formed with an annularcorrugation tioned that is of simple construction; that readily 22 whichmay be concentric with the axis of the and cheaply may be manufactured:that comwasher, and the washer is so mounted in the rubprises animproved bond between rubber and her structure that the concave side ofthe cor- 25 metal elements that strongly resist separation rugationfaces the adjacent end of the insulator. 25 thereof; and to provide aninsulator especially The washer also is formed with a concentricsesuitable for supporting a vehicle muiiler from the ries of apertures23, which apertures are located frame of the vehicle. More specifically,the inin the corrugation 22. The washers ii are of vention aims toprovide an insulator of the charslightly Smaller diameter n the ru erstrucacter mentioned comprising metal and rubber eleture so as to becompletely embedded therein, and 30 ments, which elements are united bya chemical are disposed so near the end faces of the strucand mechanicalbond. Other objects will be ture as to be covered only by a relativelythin manifest as the specification proceeds. layer of rubber, about &inch thickness of rubber Of the accompanying drawing: being suflicient.The rubber extends through the Figure 1 is a perspective view of aportion of a several apertures 23 oi the washers and unites 35 vehicleframe, a muiiler and an exhaust pipe exthe thin layers of rubber on theouter faces thereof tending from one end of the latter, and two of thewith the main rubber body. improved insulators supporting the mufflerand Each metal strap Ii that embraces the pipe Iii exhaust pipe from theframe; has an offset portion Ila, to which portion the in-- 40 Figure 2is a side elevation of the improved insulator I5 is connected, saidofiset portion being it sulator, in operative association with asupportof such radial extent that the insulator will be ing member and asupported member, the latter spaced at least one inch from the pipe l3so as being shown in section; not to be aiiected by the heat thereof.The re- Figure 3 is a vertical diametric section of the spective ends ofthe strap [4 are in spaced relation, structure shown in Figure 2; andsubstantially radially of the pipe l3 as shown, 45

Figure 4 is a section on the line 4-4 of Figure 2. and engaged by a bolt25 by means of which the Referring to the drawing, I0 is a portion of astrap is clamped upon the pipe. The offset porside rail of the frame ofa motor vehicle, H, II 9, tion Ila or the strap is formed with anaperture portion of transverse bracing members of said 26 to receive'oneof the stud bolts l8 of the inframe, i2 is a muffler of usualconstruction, [3 sulator. In connecting the insulator to the strap 50 isan exhaust pipe extending from one end of the H, a washer 21 ispositioned upon the end face muilier and constituting the outletthereof, ll, ll of the insulator, and a spacer collar 28 is posiaremetal straps about the pipe l3, and l5, [5 are tioned between the washer21 and the outer face insulators interposed betweenthe respective of theoffset portion Ma .of the strap. The in- 65 straps l4 and thecross-braces H to support the sulator and strap are secured in assembledrelation by a nut 29 mounted on stud bolt l8, within the oflset portionof the strap H. The other end of the insulator is secured to thecross-brace II by means of a nut 30 on the other stud bolt l8. Thearrangement is such that the extended axis of the insulator l5intersects the axis of the pipe l3 so that weight of the latter exertscompressive stress upon the insulator, and most vibration of the pipe istransmitted to the insulator parallel to the axis thereof.

When the insulator is mounted between supported and supporting membersas shown, and the nuts 29, 30 are set up tightly, the annular body ofrubber in each groove, defined by the corrugation 22 of each washer H,is put under high compressive stress, with the result that frictionalengagement of the rubber with the sides of said washer-grooves isincreased and an improved mechanical'bond between the metal and rubberis effected. The compressive stress on the rubber within thewasher-grooves is communicated to local regions of the insulator bodythrough the apertures 23 of the washers, the high-compression rubberconstituting, in effect, rivets that hold the washers securely to themain body of rubber.

Thus the washers are not readily torn from the insulator, as is the casewith prior art structures wherein the bonding rubber is not undercompressive stress. The invention also makes for quietness within thebody of the vehicle and achieves the other objects set out in theforegoing statement of objects.

Modification may be resorted to without departing from the spirit of theinvention, or the scope thereof as defined by the appended claim.

What is claimed is:

An insulator comprising a cylindrical body of rubber, metal washersembedded in the body and vulcanized thereto closely adjacent therespective ends thereof, each washer being formed with an annularcorrugation with the concave side thereof facing the adjacent end of therubber structure and having a plurality of apertures located therein andthrough which the rubber extends to connect with the rubber on theoutside of the washers, respective stud bolts connected to said washersand projecting axially from the opposite ends of said insulator,wherebyowhen said insulator is attached between two members with theends of the insulator held against plane surfaces by means of said boltsthe rubber outwardly of said embedded washers and in said corrugationswill be placed under compression.

CURT SAURER.

